Chapter 2: Water

Question 1

What is a polar molecule?

Answer 1

Consists of a positive and negative charge.

Question 2

is water polar or non polar?

Answer 2

polar

Question 3

water forms what kind of bonds, weak or strong, covalent or non covalent, and why

Answer 3

-hydrogen bonds
-weak
-noncovalent
-Because the hydrogen of one water molecule with its slightly positive charge can bond to another water molecule’s oxygen with a slightly negative charge

Question 4

Oxygen and hydrogen, which is positive and neg

Answer 4

Oxygen is more neg
Hydrogen is more pos

Question 5

difference between covalent and non covalent bonds

Answer 5

-covalent bonds share pair of electrons equally, strongest type of bond
noncovalent bonds have 3 types: ionic being the strongest of the 3, takes a bond away
hydrogen, second is when polar covalent bonds are attracted to each other, the last on van Der Waals is the weakest is the asymmetric distribution of electrons

Question 6

brownian motion?

Answer 6

the movement of molecules powered by random fluctuations of environmental energy
weak bond

Question 6

brownian motion?

Answer 6

the movement of molecules powered by random fluctuations of environmental energy
weak bond

Question 7

hydrophilic means?

Answer 7

polar molecules and ionic compounds dissolve in water

Question 8

hydrophobic means

Answer 8

nonpolar substances are soluble in non polar solvents
‘like dissolves like”

Question 9

electrostatic interactions is also known as

Answer 9

ionic bonds or salt bridges

Question 10

acceptors usually

Answer 10

don’t have hydrogen in them, nitrogen or oxygen

Question 11

donors usually

Answer 11

include hydrogen

Question 12

hydrogen bonds form between an

Answer 12

electronegative atom and hydrogen

Question 13

van der Waals

Answer 13

asymmetric, repulsion

Question 14

hydrophilic substances dissolve in what

Answer 14

water

Question 15

the hydrophobic effect?

Answer 15

exclusion of non polar groups to maximize the entropy of water molecules, causes protein effect

Question 16

what happens when a non polar is added to water

Answer 16

water cages the solute making the non polar aggregate

Question 17

amphiphiles come from phospholipids

Answer 17

hydrophilic head and hydrophobic tail to form cell membrane two types micelle and bilayer, fatty acid

Question 18

water moves by? solutes move by?

Answer 18

osmosis-is the net movement of solvent across the membrane from a region of high concentration (here, pure water) to a region of relatively low concentration
diffusion

Question 19

what is an acid/base

Answer 19

acid donates a proton decreases pH
base accepts a proton increases pH

Question 20

pH meaning?

Answer 20

the acidity of a solution
ph=-log[H+]
ph=7 neutral
>7 basic
<7 acidic

Question 21

higher pKa?

Answer 21

stronger acid

Question 22

if a solution contains both acid and conjugate base it is what

Answer 22

a buffer, buffers reisst pH change
determine pH using pH=pKa+log[base/acid]